Objective To investigate the effect of transurethral resection of bladder tumor (TURBT) with or without intravesical instillation therapy on cancer-specific-survival rate (CSS) of T1 stage non-muscle-invasive bladder transitional cell carcinoma (BTCC) patients.

Methods The data of patients diagnosed with T1 stage non-muscle-invasive BTCC from 2010 to 2015 were obtained from the SEER database. The different dividing groups were based on TURBT with or without intravesical instillation therapy. A 1:1 PSM method was used to balance the differences in baseline data between each group. Herein, Kaplan-Meier methods were used to draw survival curves, and the difference between OS and CSS were compared by Log rank test. In addition, univariate and multivariate Cox regressionanalyses were used to explore the independent risk factors of CSS.

Results The OS and CSS of patients in the TURBT combined with intravesical instillation therapy group were higher than those of the TURBT alone group (P < 0.05). TURBT combined with intravesical instillation therapy was a protective factor in prognosis with T1 stage non-muscle-invasive BTCC patients (HR=0.783, 95%CI: 0.650-0.942, P < 0.01).

Conclusion TURBT combined with intravesical instillation therapy improves the CSS of patients with T1 stage non-muscle-invasive BTCC.